基于LVDS电路的预加重测试

Preaggravation Test Based on LVDS Circuit

在高速LVDS集成电路的测试中,由于长距离、高速率下会带来能量损失,这种传输损耗会使信号的高频分量比低频分量损耗更大,而导致驱动能力不足等问题,故在集成电路设计中增加预加重,来补偿传输损耗。该文结合具有预加重功能的MAX3845电路,对可置位预加重管脚设置三种不同状态,通过ATE动态编程,结合预加重计算公式,计算预加重dB指数,验证电路预加重模块设计质量,进一步总结测试方法和结果。

Due to the long distance and high speed,energy loss will be brought in the test of high speed LVDS integrated circuit.The transmission loss will make the high frequency component of the signal lose more than the low frequency component,which will lead to the problem of insufficient driving capacity.Preemphasis is added in circuit design to compensate for transmission loss.Combining with MAX3845 circuit with preemphasis function,the placeable preemphasis pins are set up in three different kind of states.In the same state,the preemphasis dB index is calculated by ATE dynamic proguamming with four different levels and combined with the preemphasis calculation formula.Verify the design quality of the circuit preemphasis module,and further summarize the test methods and results.